The invention relates to devices which clamp workpieces in a centering orientation for further working and more particularly the invention relates to devices with transmissions for longitudinal movement using rods, as they are known for centering vises. For the latter a rack is inserted in a housing which rack carries along a centering clamping slide directly and on one side while deflecting a second slide on the other side by means of a pinion.
Devices for the transmission of longitudinal movement using rods are used primarily for self centering clamping in a stationary fashion. Contrary to the known rotating machine chucks rod transmissions are very advantageous for this purpose since they can be of a simple construction, they can be kept low and an introduction of force is rather easy as it involves mostly a sideways lying, longitudinal movement rod.
The known centering vises have the large drawback that they are very inflexible in regard to any variability as well as concerning different lengths and for different arrangements of the respective direction of action. Thus their field of employment is quite limited.
With regard to longitudinal variability it is known to offset chuck brackets on the centering clamping slide. This way however the longitudinal variability can be only as large as the vise itself. Unfortunately one has to forgo the centering action for larger length since a very large vise is very expensive and quite annoying in the other cases.
Concerning variability of arrangement here often cases appear for which it would be quite advantageous to clamp in a centering fashion, in several intersecting directions and independent as to each direction. However the known centering vises do not cover these cases.